Automatic feeding device for liquid fuel and the like



y 1939. T. F. SPACKMAN AUTOMATIC FEEDING DEVICE FOR LIQUID FUEL AND THE LIKE 3 Sheets-Sheet 1 L mtzzzaza Filed Noy'. 12, 1936 July 11, 1939. F, sp g m 7 2,165,585

AUTOMATIC FEEDING DEVICE FOR LIQUID FUEL AND THE LIKE Filed. Nov. 12, 1936 3 Sheets-Sheet 2 Ja e/z ZZZ Wness.

4J5 Mag y 1939. T. F. SPACKMAN 2,165,535

AUTOMATIC FEEDING DEVICE FOR LIQUID FUEL AND THE LIKE (I'll:

Patented July 11, 1939 AUTOMATIC FEEDING DEVICE FUEL AND THE LIK Thomas F. Spackman, River Grove, Ill., assignor to Stewart-Warner Corporation, Chicago, 111., a corporation of Virginia Application November 12, 1936, Serial No. 110,548

FOR LIQUID E 5 Claims.

This invention relates to liquid feeding means adapted for delivering fuel oil to a burner in which it is utilized. One purpose of the invention is to provide means for automatically controlling the delivery of fuel to meet the requiredimensioned for mating, edge to edge, with the side wall of the bowl, and thebowl having a pair of diagonally opposite corner lugs 4, 4 with threaded holes 5, 5 registering with the bolt holes 5, 6 in depressed corner sections in the web of the cover to receive bolts 1, l by which the cover H is secured in place, making a substantially dusttight joint between the side walls of the bowl and the cover flange. The bowl casting includes a partition 8 cast integrally with the bottom wall 9 branch passage 3! leads laterally for communication with .a bore 32 formed in a column 33 which is a thickened portion of the partition 8,, but extends above it and above the edges of the side walls I and II. A passage 34 leads fromments of the burner. Another object is to proand side walls It) and H, and the cover is simivide means for automatically stopping the flow larly provided with an integrally cast rib l2 posiof fuel when the demand exceeds the maximum tioned for mating, edge to edge, with the partirate of supply, as in the event of leakage in the tion 8 so that with the cover in place the enclosed fuel line or imperfect control at the burner. A space is divided into two compartments. One on further object is to prevent flooding of the appacompartment is designed to house the diaphragm ratus in the event that the float which normally pump and an electric motor for driving it, and is controls it fails to function. The invention contherefore ventilated through slots 83 formed in sists of certain features and elements of conthe bottom wall 9. Y5 struction in combination, as herein shown and de- The pump is indicated in outline at M in Fig-'- scribed and as indicated by the claims. ures 2 and 3 as surmounting a housing l5, en- In the drawings: closing suitable transmission gearing and a driv- Figure 1 is a side elevation of an apparatus eming pitman l6 seen in dotted outline in Figure 3 bodying this invention and including a covered for operating the diaphragm of the pump. The in fuel bowl, or with fuel flow connections adapted driving motor includes a laminated field ii and an to extend from a source of supply and to a burner field winding l8 seen in Figure 3, and is supto be served, ported on the casing which encloses the pump Figure 2 is a top plan view of the apparatus transmission. Said motor includes a fan It on with the cover removed. its shaft for circulating air in the compartment {23 Figure 3 is a vertical section taken as indiand preventing overheating of the motor and .25

cated at the line 3-3 on Figure 1. associated parts.

Figure 4 is a top plan view of the cover. The apparatus, being designed particularly for Figure 5 is an inverted or bottom plan View of association with a stove heated by an oil burner, the cover. is arranged to be mounted in convenient relation M Figure 6 is a detail section of the cover taken e Steve, and o this purpose the bottom as indicated at line 6-6 on Figure 4. wall 9 of the bowl is formed with a hollow boss Figure 7 i a b tt m vi w of the bo l r recep- 20 adapted for securement to the end of a suittacle, able post 2| upstanding from the floor of the Figure 8 is a top plan view of the bowl with space in which the stove is located. The boss I the mechanism removed. may be provided with set screws 22 for securely Figure 9 is a vertical section taken substana t n e b to the P A fuel fiO tially as indicated at line 9-9 on Figure 8. connection from the fuel source is indicated by a Figure 10 is a detail section showing the pump P pe 0 t b n 23 l a o he bottom Of the valves and taken as indicated at line Ill-Ill on bowl by way of a coupling nipple 2 1 secured in a in Figure 3. boss 25 formedon the bottom wall 9. The out- Figure 11 is an end elevation of the bowl or low C nnect o s S OW as a p p 6 extending receptacle casting. from a coupling nipple 2! in the bottom of the Figure 12 i a d tail s ction n an enlarged bowl, and a third pipe 28, connected into a conscale to show the construction of the automatic pling 29. serves as an overflow connection for leak or Vent. returning fuel to the supply tank (not shown). As shown, the apparatus is housed in a metallic Th s ov w is h fly for h p p of carrycasing which may be a casting of any suitable ng ofi Surp us e Which m t b poured in metal, as for example, a die casting, and is when the pump is being primed. shown in the form of a rectangular bowl I' with In the boss '25, the coupling nipple 2 enters an a cover 2, the cover being formed with a flange 3 upwardly extending passage 39, from which a 50 the bore 32 to the inlet port 35 for the pump, said port being formed in a plug 36, which also houses the inlet valve 31. A substantially similar plug 38 contains the outlet port 39 and outlet valve 40 and these two plugs serve as securing means for fastening the pump head casting 4| aaginst the upper end portion of the column 33, as seen in Figure 3. The inlet passage is restricted by the insertion of a threaded plug 42 in the lower end of the bore 32, said plug having a transverse passage 43 which communicates with the passage 3|, and having also a central restricted passage 44 through which the oil must flow upwardly to reach the pump, and through which suction is exerted on the oil line by the pump.

It may be understood that the pump is of the diaphragm type, the diaphragm itself not being shown in detail, but indicated at 45 as clamped between the head casting 4i and a flange 46 at the upper end of the transmission casing. The diaphragm movement serves to draw liquid fuel in through the port 35 and expel it through the outlet port 39 which communicates with a discharge passage 41 leading downwardly from the pump connection through the column 33 and opening into a notch or recess 48 in the bottom of the column just above the bottom wall- 9 of the bowl. In this way the fuel compartment 49 is filled with liquid up to the predetermined level at which the accumulation of fuel is to be arrested. This may be substantially at the level of overflow ports 59 formed in a covered well 5| in the bowl casing. The coupling nipple 29 connects this well with the overflow pipe 25 leading back'to the supply tank.

As will be seen from Figure 8, the compartment 49 of the bowl which is defined by the partition 8 therein, is L-shaped in plan section, and includes an alcove 52 which accommodates the float 53 whose function is to control operation of the motor which drives the pump. As the liquid fuel accumulates in the compartment 49 and its alcove 52, the float 53 is buoyed up until, upon reaching a predetermined level, its connected rod 54 operating upon the crank 55 of a rock shaft 56 swings the tube 51 of a mercury switch to the angle at which it cuts off the current from the motor and thus halts the operation of the pump for the time being. When the fuel level in the space 52 recedes to a predetermined point, the switch 51 being rocked by the descent of the float 53 re-establishes the driving circuit for the motor, and the pump is again placed in operation to replenish the supply of liquid fuel in the bowl. The provision for current supply for the motor is indicated by the cable 58 with suitable connecting wires leading therefrom to the switch 51 and to the motor, as shown in Figure 2, but which need not be described in detail.

If a defect in the burner, or a leak in the pipe line 25 should cause the fuel to be withdrawn from the compartment 49-52, at an excessive rate, the result would be that either the burner would operate in an inefiicient manner with incomplete combustion, or the unburned fuel would be spilled upon the floor adjacent the furnace, with a resultant fire hazard. There being no chance for the liquid to accumulate in the bowl, the float 53 would not be lifted to its upper limit, and the switch 51 would not be operated to stop the motor and pump. Under these conditions, it is desirable that the continued operation of the 'pump shall not continue to draw liquid fuel from it into the compartit would continue to the supply source and pass ment 4952 from which flow through the leak in the line, or into the defective burner. Therefore, the inlet passage 30 is provided with a second lateral branch 59 connecting into a passage 60 which leads upwardly adjacent the float 53 and which is threaded at 61 to receive a threaded plug 62. The threads of the plug 62 are fitted loosely in the threads 6| of the passage so as to provide an air leak around said threads, as clearly shown in Figure 12. When the liquid level in the space 52 recedes below the upper end of the passage 60 the suction of the pump acting through the bore 32 and lateral passages 3| and 59 will be satisfied by air drawn in past the threads GI and will fail to lift the liquid fuel through the supply line 23. The remaining liquid in the space 49-52 will be depleted rapidly through the delivery pipe 26 and thereafter no more oil will be delivered from the apparatus. The burner will consequently cease to operate, and the condition will presently come to the attention of the occupants of the building or the janitor in charge of the heating plant, without resulting in any serious fire hazard.

The air leak around the threads of the plug 62 also becomes effective in the event that the float 53 becomes perforated, or for some other reason loses its buoyancy and falls below the normal lower limit of its range to the position shown in full lines in Figure 9. In the case of a defective float, this may occur before the level of the liquid has receded below the upper end of the passage 59; therefore, the plug 62 supports an upstanding guide rod 53 on which there is carried a loosely fitting sleeve 54 whose upper flange 65 normally rests on a forked arm 56 extending more or less rigidly from the heat 53 and holding the lower flange 6'! of the sleeve 64 above the upper end of the passage 60. But when failure of the fioat allows it to descend below the normal low limit of its range, the sleeve 64 is lowered onto the upper surface of the boss in which the passage 60 is formed, and the sleeve 94- thus becomes an extension of the passage reaching above the level of liquid in the chamber 52 and conducting air to the upper end of the passage 69 and thence through the air leak around the threads of the plug 62. Thus enough air is supplied through the branch 59 to the intake 34 of the pump to satisfy suction of the pump and prevent more liquid from being drawn in through the inlet pipe 23. Presently, the supply of liquid in the space 49-52 will be depleted by the burner, and the latter will cease to operate, calling attention to the fact that the device is out of order and requires attention.

The air leak afforded by the looseness of the threads of the plug 62 in the threaded bore 6! may be made adjustable in various ways. As shown in Figure 12, the threads Bl are formed in a bushing 68 fitting tightly in the upper end of the passage 60 but of substantially the same length as the plug 62. Thus, when the plug is screwed downwardly so that a portion of it protrudes from the lower end of the bushing into the larger bore 68, the effective length of the helical air vent between the threads which are still in engagement is reduced, and the friction of the vent passage is thus reduced so as to vary its effect as a vent. A spring 69 pocketed in the lower portion of the passage 60 bears against the lower end of the plug 62 for holding it in adjusted position.

To ensure the elimination of dirt from the liquid fuel the plug 42 is formed with a reduced portion registering with its transverse passage 43 and an annular screen 10 is secured in the recess thus formed in the surface of the plug. Occasionally, it may be necessary to prime the apparatus in starting it, and for this purpose the cover is formed with a filler opening fitted with a screen 7! through which liquid can be poured in; the opening is provided with a swinging cover ?2 and registers with the L-shaped compartment 59-52 in which the liquid is accumulated, and from which it flows to the burner or other point of use.

From Figure 3 it will be noted that the heads of the plugs 36 and 38 engage one side of the column 33 while their threaded ends draw the pump body against the other side of the column, and that this provides the sole support of the pump in the receptacle or housing I but entirely out of contact with its walls. This arrangement tends to ensure quietness of operation because any tendency to vibration is absorbed in the motor and pump structure before it leaves the housing hence, the housing does not contribute any resonance or amplifying effect in the event of such vibration.

While there is shown and described herein certain specific structure embodying the invention, it will be manifest to those skilled in the art that various modifications and re-arrangements of the parts may be made without departing from the spirit and the scope of the invention, and that the same is not limited to the particular form herein shown and described, except in so far as indicated by the appended claims.

I claim:

1. In a liquid feeding device, a pump, an electric motor connected to drive the pump, a chamber into which the pump delivers the liquid, a float in the chamber responsive to changes of liquid level therein, and an electric switch for the motor connected for actuation by said float, a suction line leading to the pump and a vent passage from said line having an opening in the chamber but normally submerged by the liquid therein, an extension tube for said vent, normally disconnected therefrom and means actuated by the descent of the float below its normal lower limit serving to connect the extension to the vent for shifting the effective vent opening to a higher level.

2. In a liquid feeding device, a pump, an electric motor connected to drive the pump, a chamber into which the pump delivers the liquid, a float in the chamber responsive to changes of liquid level therein, and an electric switch for the motor connected for actuation by said float, a suction line leading to the pump and a vent passage from said line having an opening in the chamber but normally submerged by the liquid therein, said vent passage opening upwardly, an extension tube carried by the float above the vent opening throughout the normal range of float movement but adapted to be lowered into connection with said opening when the float falls below its normal low limit, whereby the effective vent opening is shifted to a higher level.

3. In a liquid feeding device, a pump, an electric motor connected to drive the pump, a chamber into which the pump delivers the liquid, a float in the chamber responsive to changes of liquid level therein, and an electric switch for the motor connected for actuation by said float, a suction line leading to the pump and a vent passage from said line having an opening in the chamber but normally submerged by the liquid therein, said vent passage includinga threaded bore and a threaded plug loosely fitted and axially adjustable therein, a guide rod extending upwardly from the plug, a tube loosely slidable on said rod and an arm on the float engaging the tube normally supporting it above the opening of the vent but adapted to lower the tube into connection with said opening when the float falls below its normal low limit, whereby the effective vent opening is shifted to a higher level.

4. In a liquid feeding device, a receptacle provided with a vertical partition dividing it into two compartments, an electric motor and a pump driven thereby in one compartment, the other compartment serving asa receiving chamber for the liquid, the partition having a pair of vertical passages, an inlet connection leading from a liquid supply source into the lower end of one passage, the other passage having a discharge opening in the lower part of the receiving chamber, the partition having a pair of transverse passages into which the upper ends of the vertical passages respectively open, the transverse passages connecting with intake and discharge ports respectively of the pump, said transverse passages extending through the partition, and hollow plugs each having a head at one end and having its opposite end threaded for supporting the pump body on the partition, said plugs having passages which connect the passages of the partition with the ports of the pump.

5. In a liquid feeding device, a receptacle provided with a vertical partition dividing it into two compartments, an electric motor and a pump driven thereby in one compartment, the other compartment serving as a receiving chamber for the liquid, said partition having a pair of vertical passages, an inlet connection leading from a liquid supply source into the lower end of one passage, the other passage having a discharge opening in the lower part of the receiving chamber, the partition having also a pair of transverse openings near the top, the pump including a body portion containing inlet and exhaust ports and fitted against said partition at one side, a pair of hollow plugs extending through said transverse openings having heads engaging the opposite side of the partition with internal passages respectively connecting the vertical passages of the partition with the ports of the pump and having threaded end portions engaging in the pump body for supporting it, said connection providing the sole support for the pump in the receptacle, and means by which the motor is mounted upon the pump body and wholly supported thereby out of contact with the walls of the receptacle.

THOMAS F. SPACKMAN. 

